PlantPlant

ComponentComponent

Media Filters

Cartridge Filter

High Pressure

Pump

Permeate Line

Storage TankTransient

Tank

FiltratedTank

RawWaterTank

FromWater

SourceSea/Wells Filtrated

Pump

Feed

Pump

RO Module

Cleaning &

Flushing Pump

Transfer

Pump

Reject

Line Cleaning

Tank

The The Raw water is being drawn to the Plant from two Raw water is being drawn to the Plant from two sources:sources:

Open Intake (Open Intake (Sea WaterSea Water).).

Beach Wells (Beach Wells (Bore WellBore Well).).

Water SourceWater Source

Feed water tank is filled by intake pumps (Bore Feed water tank is filled by intake pumps (Bore well pump / Centrifugal pump)well pump / Centrifugal pump)

Water is pumped from the tank to multi-media Water is pumped from the tank to multi-media filters by feed pump.filters by feed pump.

Install some devices in tank to measure water Install some devices in tank to measure water level, water conductivity and water pH inside tank.level, water conductivity and water pH inside tank.

The feed water pump is pumping the raw water to The feed water pump is pumping the raw water to pass through multi-media filters.pass through multi-media filters.

Feed Water Tank, Feed Water Tank, PumpPump

The most common filter media in water treatment are The most common filter media in water treatment are sand and anthracite, The effective grain size for fine sand and anthracite, The effective grain size for fine sand filter is in the range of (0.35 to 0.5 mm) and sand filter is in the range of (0.35 to 0.5 mm) and (0.7 to (0.7 to 0.8 mm) for 0.8 mm) for anthracite filter.anthracite filter.

The design filtration flow rates are usually 10–20 mThe design filtration flow rates are usually 10–20 m33/h /h and backwash rates are in the range 40-50 and backwash rates are in the range 40-50 mm33//h.h.

The removal of suspended and colloidal particles by The removal of suspended and colloidal particles by media filtration is based on their deposition on the media filtration is based on their deposition on the surface of filter grains, the quality of the filtrate depends surface of filter grains, the quality of the filtrate depends on the size, surface charge and geometry of both on the size, surface charge and geometry of both suspended solids and filter media, as well as on the water suspended solids and filter media, as well as on the water analysis and operational parameters.analysis and operational parameters.

Multi Media FiltersMulti Media Filters

Feed Line

Filtrated Line

DrainDrain

MF1

TIT1037

AIT1037

26.1 °C

0.13 NTUTurbidity

Service Inlet

FV-1060-1

FCV-1066-1

FIT1020-1

100.00 m3/h

Service OutletTo Cartridge

Filters

FV-1065-1

FV-1063-1

FV-1061-1

B-85 FV-1064-1

Air Blower

90.2 %LIT8126

LIT8126

0.0 m3/h

P81A

P81B

FV-1062-1

Backwash Inlet

From Mesh FilterFV-8160

Backwash SequenceBackwash SequenceBackwash SequenceBackwash Sequence

Drain down 18001800 sec.Drain down 18001800 sec.

Air Scour 600600 sec.Air Scour 600600 sec.

Backwash 600600 sec.Backwash 600600 sec.

Rinse 600600 sec.Rinse 600600 sec.

HoldHold

TimeTime

180016001400120010008006004002000

Air ScourAir Scour

600

80.00 m3/h60.00 m3/h40.00 m3/h20.00 m3/h0.00 m3/h

BackwashBackwash

5004003002001000TK-8187.3 %TK-8180.2 %TK-8170.5 %

TK-8160.1 %

FiltratedTank48.4 %6005004003002001000

RinseRinse

6005004003002001000

Back

If The Time in drain is not enough push to the key HoldIf The Time in drain is not enough push to the key Hold

ContinueContinueHoldHold

FilterIn Service

Back Wash SequenceBack Wash Sequence

Filtrated Tank, PumpFiltrated Tank, Pump

Filtrated water tank is filled from multi-media Filtrated water tank is filled from multi-media filters.filters.

Water is pumped from the tank to cartridge filter Water is pumped from the tank to cartridge filter by using filtrated pump.by using filtrated pump.

Install some devices in tank to measure water Install some devices in tank to measure water level, water conductivity and water pH inside tank.level, water conductivity and water pH inside tank.

The filtrated water pump is pumping the filtrated The filtrated water pump is pumping the filtrated water to pass through cartridge filter.water to pass through cartridge filter.

Cartridge FilterCartridge Filter It’s It’s safety device to protect the membranes and the safety device to protect the membranes and the

high pressure pump from suspended particleshigh pressure pump from suspended particles.. Cartridge filter with a pore size of less than 10 Cartridge filter with a pore size of less than 10

Micron is minimum pretreatment required for every Micron is minimum pretreatment required for every RO systemRO system..

It should be made of a synthetic non degradable It should be made of a synthetic non degradable material e.g. Nylon or Polypropylenematerial e.g. Nylon or Polypropylene..

It should be equipped with a pressure gauge to It should be equipped with a pressure gauge to indicate the differential pressure drop and thereby indicate the differential pressure drop and thereby indicating the extent of its fouling and replace the indicating the extent of its fouling and replace the filter needle before pressure drop has increased to filter needle before pressure drop has increased to the permitted limit, But latest after 3 months.the permitted limit, But latest after 3 months.

High Pressure PumpHigh Pressure Pump

It’s a pump used to lift filtrated pump pressure to It’s a pump used to lift filtrated pump pressure to high pressure used to discharge a cross high pressure used to discharge a cross membrane element to product permeate water.membrane element to product permeate water.

It’s two kind of high pressure pumps:It’s two kind of high pressure pumps:

Centrifugal PumpCentrifugal Pump

Positive displacementPositive displacement

Centrifugal PumpCentrifugal Pump It’s a Centrifugal pumps use a spinning impeller to force It’s a Centrifugal pumps use a spinning impeller to force

water to the outside of the pump casing.water to the outside of the pump casing.

The energy present in this centrifugal force is translated The energy present in this centrifugal force is translated into water pressure as the water exits the pump.into water pressure as the water exits the pump.

Single stage centrifugal pumps are commonly used for Single stage centrifugal pumps are commonly used for lower pressure applications, usually less than 80 pounds lower pressure applications, usually less than 80 pounds per square inch (psi).per square inch (psi).

Higher pressures are possible with higher rotational Higher pressures are possible with higher rotational speeds, but some energy efficiency is lost due to the speeds, but some energy efficiency is lost due to the additional shear on the water from the high speeds.additional shear on the water from the high speeds.

Multistage centrifugal pumps can create pressures up to Multistage centrifugal pumps can create pressures up to 600 psi more efficiently by using a number of impellers 600 psi more efficiently by using a number of impellers in series.in series.

The impellers are all attached to a long shaft that is spun The impellers are all attached to a long shaft that is spun by the pump motor.by the pump motor.

Each impeller increases the water pressure some 15 to 25 Each impeller increases the water pressure some 15 to 25 psi from the pressure provided by the previous impeller.psi from the pressure provided by the previous impeller.

Between the impellers, diffuser bowls direct the water Between the impellers, diffuser bowls direct the water from the outside of the casing back to the center of the from the outside of the casing back to the center of the next impeller.next impeller.

Multistage centrifugal pumps are used deep in the Multistage centrifugal pumps are used deep in the ground as well pumps.ground as well pumps.

These pumps use submersible motors that are protected These pumps use submersible motors that are protected from the water passing around them.from the water passing around them.

These submersible pump/motor units can be installed These submersible pump/motor units can be installed within a pressure vessel and used with RO systems as a within a pressure vessel and used with RO systems as a means of reducing the noise created by the high pressure means of reducing the noise created by the high pressure pumps.pumps.

They typically offer greater pump energy efficiency, but They typically offer greater pump energy efficiency, but this gain is usually offset by the reduced efficiency of this gain is usually offset by the reduced efficiency of using water-cooled motors .using water-cooled motors .

Centrifugal PumpCentrifugal Pump

Piston PumpPiston Pump It’s For creating pressures greater than 600 psi, as It’s For creating pressures greater than 600 psi, as

required for seawater reverse osmosis systems, piston required for seawater reverse osmosis systems, piston pumps are often used.pumps are often used.

Mechanical plungers compress the water to achieve the Mechanical plungers compress the water to achieve the desired output pressure.desired output pressure.

Check valves direct the flow of water in the desired Check valves direct the flow of water in the desired direction.direction.

Piston pumps use a number of plungers/pistons that are Piston pumps use a number of plungers/pistons that are attached to a rotating shaft which is driven by a motor.attached to a rotating shaft which is driven by a motor.

By using a number of pistons, the pulsing of the output By using a number of pistons, the pulsing of the output pump pressure is reduced.pump pressure is reduced.

This pulsing causes velocity surges that promote This pulsing causes velocity surges that promote telescoping and mechanical damage of the RO telescoping and mechanical damage of the RO membrane elements.membrane elements.

Even with multiple pistons, a pressure surge dampening Even with multiple pistons, a pressure surge dampening device should be used between the piston pump and the device should be used between the piston pump and the RO system.RO system.

Since a seawater RO system that uses a piston pump Since a seawater RO system that uses a piston pump usually operates at permeate recoveries less than 50%, usually operates at permeate recoveries less than 50%, its relatively large concentrate stream contains a great its relatively large concentrate stream contains a great deal of potential energy.deal of potential energy.

Much of this can be used to reduce the pump Much of this can be used to reduce the pump requirements for the feed water with an energy recovery requirements for the feed water with an energy recovery device.device.

Piston PumpPiston Pump

Pressure VesselPressure Vessel

It’s It’s a tube made from fiber used to charge by a tube made from fiber used to charge by membrane elements.membrane elements.

Inside pressure vessel three types of water (Feed, Inside pressure vessel three types of water (Feed, Permeate and Concentrate).Permeate and Concentrate).

Pressure vessel available with different diameters, Pressure vessel available with different diameters, length and pressure rating.length and pressure rating.

Diameter from 1.5Diameter from 1.5 to 2.5to 2.5 available pressure from 85 to 1000 psi. available pressure from 85 to 1000 psi.Diameter 4Diameter 4 available pressure from 600 to 1000 psi. available pressure from 600 to 1000 psi.Diameter 8Diameter 8 available pressure from 400 to 1000 psi. available pressure from 400 to 1000 psi.

Replace Membrane Replace Membrane ElementElement

As with replacing O-rings, the system should first be As with replacing O-rings, the system should first be shut down and drained.shut down and drained.

Prior to installation, the new element serial numbers Prior to installation, the new element serial numbers should be recorded indicating their intended location in should be recorded indicating their intended location in the system.the system.

This is often useful in comparing the membrane This is often useful in comparing the membrane manufacturer's test data with the system performance.manufacturer's test data with the system performance.

With multi-element pressure vessels, it may be necessary With multi-element pressure vessels, it may be necessary to remove both of the vessel end caps.to remove both of the vessel end caps.

The elements can then be removed in their normal The elements can then be removed in their normal direction of flow.direction of flow.

This will prevent their brine seals from jamming against This will prevent their brine seals from jamming against the pressure vessel.the pressure vessel.

The replacement element (s) can be inserted in the feed The replacement element (s) can be inserted in the feed end of the vessel and used to push the other elements end of the vessel and used to push the other elements through.through.

After element replacement, any gaps should be limited After element replacement, any gaps should be limited with shims.with shims.

The end caps can then be installed and the system The end caps can then be installed and the system started up.started up.

It should be filled with low pressure water prior to It should be filled with low pressure water prior to starting the high pressure pump.starting the high pressure pump.

New elements should be rinsed to drained to remove any New elements should be rinsed to drained to remove any residual chemicals.residual chemicals.

System operating data should be collected after the RO System operating data should be collected after the RO performance stabilizes.performance stabilizes.

If it is intended to autopsy or re-use the elements that are If it is intended to autopsy or re-use the elements that are removed, they should be treated carefully.removed, they should be treated carefully.

They should not be placed on end on a hard surface that They should not be placed on end on a hard surface that may damage plastic parts.may damage plastic parts.

They should also be sealed in a bag to prevent them from They should also be sealed in a bag to prevent them from drying out.drying out.

A biocide may be added for long-term storage .A biocide may be added for long-term storage .

RO ModuleRO Module RO Vessel is Fabricate from Fiber to carry High RO Vessel is Fabricate from Fiber to carry High

pressure 80 bar (1200 psi).pressure 80 bar (1200 psi). Spiral wound, hollow fiber, and tubular elements Spiral wound, hollow fiber, and tubular elements

require some sort of pressure vessel to house their require some sort of pressure vessel to house their particular membrane configuration.particular membrane configuration.

The vessel must be designed to contain the high The vessel must be designed to contain the high pressure required for reverse osmosis.pressure required for reverse osmosis.

With spiral wound systems, pressure vessels/housings With spiral wound systems, pressure vessels/housings are available to hold up to eight 40 inch elements are available to hold up to eight 40 inch elements connected end to end.connected end to end.

To prevent water from bypassing around the outside of To prevent water from bypassing around the outside of the elements, a sealing device called a brine seal is the elements, a sealing device called a brine seal is placed around the element.placed around the element.

This brine seal is usually "V" shaped so that the flowing This brine seal is usually "V" shaped so that the flowing water forces the "V" to flare out and seal against the water forces the "V" to flare out and seal against the inside wall of the vessel.inside wall of the vessel.

To attach the central permeate collection tube from one To attach the central permeate collection tube from one element to the next, an inter-connector is used.element to the next, an inter-connector is used.

This inter-connector uses O-rings, sometimes two on This inter-connector uses O-rings, sometimes two on each end, to assure sealing integrity between the each end, to assure sealing integrity between the elements.elements.

Any leak will result in the high pressure water and its Any leak will result in the high pressure water and its dissolved ions bypassing directly into the permeate dissolved ions bypassing directly into the permeate lines.lines.

A similar type of end connector attaches each of the A similar type of end connector attaches each of the end element's permeate tubes to the permeate port of end element's permeate tubes to the permeate port of the vessel's end cap. the vessel's end cap.

Permeate TankPermeate Tank

A permeate tank is typically employed, when the A permeate tank is typically employed, when the permeate is the product.permeate is the product.

Plant start-ups and shut-downs are initiated by Plant start-ups and shut-downs are initiated by low-level and high-level signals from the permeate low-level and high-level signals from the permeate tank.tank.

The system capacity and the tank size should be The system capacity and the tank size should be designed so that the RO plant is allowed to run for designed so that the RO plant is allowed to run for some hours continuously.some hours continuously.

The less frequently the plant is shut down, the The less frequently the plant is shut down, the better is the system performance.better is the system performance.